Facebook explains what advertisers know about you

Facebook is still facing heat over its privacy controls in the wake of the Cambridge Analytica scandal, and it's trying to reassure users that their personal info isn't on the open market. The social network has posted a detailed Q&A explaining just what advertisers know about you -- and importantly, what they don't. It stressed that it doesn't personally identify you, and that it's only selling "space" for ads in the same way a TV network might, not the data itself. Marketers get the generic demographics for their ads, the pages you like, the articles you visit and information they already had from elsewhere (such as existing purchases or a third-party app).

The company also emphasized that you can opt out of ad targeting (though not advertising as a whole). It also insists that its social network is the product, not you -- it's the "ability to connect" that matters, Facebook said.

While these are important points and may help assuage the fears of those convinced Facebook is harvesting every ounce of personal data, it doesn't entirely address the concerns that prompted Mark Zuckerberg's testimony before Congress. The concern wasn't that Facebook was selling data, but that it didn't keep close tabs on what data apps could collect ("Thisisyourdigitallife" collected info about users' friends without consent) and didn't notify users when it discovered that the data had been compromised.

And while Facebook is refuting the notion that it's treating users as products, it's still true that Facebook's business model revolves around advertising -- with customized ads whenever possible. That's why ad targeting is opt-out rather than opt-in, after all. It might be difficult to completely escape privacy concerns so long as Facebook has reason to share something about you, even if it's something as simple as a page like.